<html>
<head><meta charset="utf-8"><title>subgoal_cycle_uninhabited · wg-traits · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/index.html">wg-traits</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html">subgoal_cycle_uninhabited</a></h3>

<hr>

<base href="https://rust-lang.zulipchat.com">

<head><link href="https://rust-lang.github.io/zulip_archive/style.css" rel="stylesheet"></head>

<a name="184956679"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956679" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956679">(Jan 06 2020 at 21:09)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> Can you see what's wrong with the program here: <a href="https://github.com/rust-lang/chalk/pull/317/files#diff-89813e240fc3a9c6dc98c7a56b209353R191" target="_blank" title="https://github.com/rust-lang/chalk/pull/317/files#diff-89813e240fc3a9c6dc98c7a56b209353R191">https://github.com/rust-lang/chalk/pull/317/files#diff-89813e240fc3a9c6dc98c7a56b209353R191</a></p>



<a name="184956741"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956741" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956741">(Jan 06 2020 at 21:10)</a>:</h4>
<p>It's identical to this <a href="https://github.com/rust-lang/chalk/pull/317/files#diff-89813e240fc3a9c6dc98c7a56b209353R248" target="_blank" title="https://github.com/rust-lang/chalk/pull/317/files#diff-89813e240fc3a9c6dc98c7a56b209353R248">https://github.com/rust-lang/chalk/pull/317/files#diff-89813e240fc3a9c6dc98c7a56b209353R248</a> except for the impl</p>



<a name="184956770"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956770" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956770">(Jan 06 2020 at 21:10)</a>:</h4>
<p>But gives me a well-formed error</p>



<a name="184956809"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956809" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956809">(Jan 06 2020 at 21:10)</a>:</h4>
<p>(or if I add the impl, an overlapping impl error)</p>



<a name="184956815"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956815" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956815">(Jan 06 2020 at 21:10)</a>:</h4>
<p>I think the slg tests didn't run the WF checks</p>



<a name="184956831"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956831" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956831">(Jan 06 2020 at 21:10)</a>:</h4>
<p>but I'm not sure</p>



<a name="184956843"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956843" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956843">(Jan 06 2020 at 21:10)</a>:</h4>
<p>I was just checking on that</p>



<a name="184956912"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956912" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956912">(Jan 06 2020 at 21:11)</a>:</h4>
<p>yes, I checked and it seems they did</p>



<a name="184956924"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956924" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956924">(Jan 06 2020 at 21:11)</a>:</h4>
<p>it called <code>checked_program</code></p>



<a name="184956951"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956951" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956951">(Jan 06 2020 at 21:11)</a>:</h4>
<p>yeah ok I see that</p>



<a name="184956959"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184956959" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184956959">(Jan 06 2020 at 21:11)</a>:</h4>
<p>I take it back then :)</p>



<a name="184957027"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184957027" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184957027">(Jan 06 2020 at 21:12)</a>:</h4>
<p>I'm just really confused</p>



<a name="184957065"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184957065" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184957065">(Jan 06 2020 at 21:12)</a>:</h4>
<blockquote>
<p>But gives me a well-formed error</p>
</blockquote>
<p>what is the error exactly?</p>



<a name="184957142"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184957142" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184957142">(Jan 06 2020 at 21:13)</a>:</h4>
<p><code>thread 'test::misc::subgoal_cycle_uninhabited' panicked at 'called `Result::unwrap()` on an `Err` value: ChalkError { error_text: "trait impl for `Foo` does not meet well-formedness requirements" }'</code></p>



<a name="184957149"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184957149" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184957149">(Jan 06 2020 at 21:13)</a>:</h4>
<p>oops formatting</p>



<a name="184957708"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184957708" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184957708">(Jan 06 2020 at 21:19)</a>:</h4>
<p>so if you add the second impl, you get an overlap error?</p>



<a name="184957976"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited/near/184957976" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/subgoal_cycle_uninhabited.html#184957976">(Jan 06 2020 at 21:22)</a>:</h4>
<p>yes</p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
</html>